extraneous files

I would like to move all desktop:~/Downloads/*.avi files from my desktop to laptop:~/Download/ using rsync. How do I delete source file after successful transfer is done using rsync command under BSD/Unix/Linux/Apple OS X operating systems?

so if the file doesn’t change, the next snapshot is simply a hard link to the exact same file. How do I use the rsync command to copy my the entire snapshot directory /raid6/rsnapshot (around 4TB) to a remote server?